The entity relationship (ER) data model is widely used for logical data modeling. It supports data modeling at the business level in terms of entities, attributes and relationships. ER data models are valuable assets to an enterprise because they represent the enterprise's information model and serve as the common base for generating or correlating various physical data assets, such as physical data models representing relational databases or eXtensible Markup Language (XML) schemas.
XML is a widely used standard for data interchange among diverse devices, applications, and systems across industries and sectors. The volume of XML data that organizations must handle is growing exponentially. As such, XML data now needs storage and management services with the same reliability, availability, and scalability afforded to traditional data assets. Also, XML data might have to be integrated with traditional data. The XML data and documents may contain valuable information such as customer details, transaction data, order records, and operational documents. Often the metadata for such information already exists in enterprise ER data models. The enterprise may wish to define the metadata in ER data models redundantly in XML schemas to facilitate data interchange or to capture business metadata in XML schemas redundantly in ER data models to facilitate metadata governance. At times part of this metadata might need to be manifested as XML schemas for use in applications and XML data stores, alongside those manifested as physical data models for use in designing traditional relational databases.